Whether the laws of physics would allow something like this to happen, I do not know, but Jin Woo Han's faucet dynamo concept for powering small electric devices with water power is a neat idea.

Even if it took a few weeks to accumulate enough of a charge from your daily faucet use to do anything useful with, for the right application (like slowly recharging a battery), this is cool. [Coroflot via Gadget Lab]